diff --git a/src/mzscheme/configure.ac b/src/mzscheme/configure.ac
index aa0b2dad4f..ff0c2aef63 100644
--- a/src/mzscheme/configure.ac
+++ b/src/mzscheme/configure.ac
@@ -79,6 +79,7 @@ AC_ARG_ENABLE(libfw,   [  --enable-userfw         install Mac OS X frameworks to
 AC_ARG_ENABLE(macprefix, [  --enable-macprefix      allow --prefix with a Mac OS X install])
 AC_ARG_ENABLE(mac64,   [  --enable-mac64          do not force 32-bit build])
 
+AC_ARG_ENABLE(gc2_places_testing,  [  --enable-gc2-places-testing         compile gc2 places tesging support])
 
 ###### Get OS Type #######
 
@@ -152,6 +153,12 @@ else
   fi
 fi
 
+if test "${enable_gc2_places_testing}" = "yes" ; then
+  enable_shared=yes
+  enable_places=yes
+fi
+
+
 # Hack for the implementor:
 if test "${enable_perl}" = "" ; then
   if test "$USER" = "mflatt" ; then
@@ -295,6 +302,7 @@ show_explicitly_disabled "${enable_jit}" JIT
 show_explicitly_disabled "${enable_foreign}" Foreign
 
 show_explicitly_enabled "${enable_places}" Places
+show_explicitly_enabled "${enable_gc2_places_testing}" "GC2 Places Testing"
 show_explicitly_enabled "${enable_futures}" Futures
 show_explicitly_disabled "${enable_futures}" Futures
 
@@ -983,6 +991,12 @@ if test "${endianness}" = "big" ; then
   AC_DEFINE(SCHEME_BIG_ENDIAN,1,[Big endian])
 fi
 
+############### GC2_PLACES_TESTING ###################
+
+if test "${enable_gc2_places_testing}" = "yes" ; then
+  AC_DEFINE(GC2_PLACES_TESTING,1,[GC2 Places Testing])
+fi
+
 ############### places ###################
 
 if test "${enable_places}" = "yes" ; then
diff --git a/src/mzscheme/gc2/newgc.c b/src/mzscheme/gc2/newgc.c
index c4479e863a..b5c97b36d7 100644
--- a/src/mzscheme/gc2/newgc.c
+++ b/src/mzscheme/gc2/newgc.c
@@ -470,6 +470,9 @@ int GC_is_allocated(void *p)
   return !!pagemap_find_page(gc->page_maps, p);
 }
 
+#ifdef GC2_PLACES_TESTING
+#include "testing.c"
+#endif
 
 /*****************************************************************************/
 /* Allocation                                                                */
diff --git a/src/mzscheme/gc2/testing.c b/src/mzscheme/gc2/testing.c
new file mode 100644
index 0000000000..6e2aee6107
--- /dev/null
+++ b/src/mzscheme/gc2/testing.c
@@ -0,0 +1,83 @@
+
+int GC_is_live(void *p)
+{
+  NewGC *gc = GC_get_GC();
+  mpage *page = pagemap_find_page(gc->page_maps, p);
+  if (!page) { /* NOT GC ALLOCATED */
+    printf("%p page: %p NOT GC ALLOCATED\n", p, page);
+    fflush(stdout);
+    return 0; 
+  }
+  else if (page->generation == 0) {
+    if (page == gc->gen0.curr_alloc_page) {
+      if (p < (void*) GC_gen0_alloc_page_ptr) {
+        printf("GEN0 object %p page: %p gen: %i class: %i ALIVE\n", p, page, page->generation, page->size_class);
+        printf("%p BEGIN: %p ALLOCED_UPTO: %p END: %p\n", p, (void*) gc->gen0.curr_alloc_page->addr, (void*) GC_gen0_alloc_page_ptr, (void*) GC_gen0_alloc_page_end);
+        fflush(stdout);
+        return 1;
+      }
+      else {
+        printf("GEN0 object %p page: %p gen: %i class: %i DEAD\n", p, page, page->generation, page->size_class);
+        printf("%p BEGIN: %p ALLOCED_UPTO: %p END: %p\n", p, (void*) gc->gen0.curr_alloc_page->addr, (void*) GC_gen0_alloc_page_ptr, (void*) GC_gen0_alloc_page_end);
+        fflush(stdout);
+        return 0;
+      }
+    }
+    return NUM(p) < (NUM(page->addr) + page->size);
+  }
+  else { /* page->generation */
+    if (page->size_class == 1) {
+      int dead = OBJPTR_TO_OBJHEAD(p)->dead;
+      printf("MEDIUM object %p page: %p gen: %i class: %i dead: %i\n", p, page, page->generation, page->size_class, dead);
+      fflush(stdout);
+      return !dead;
+    }
+    else if((NUM(page->addr) + page->size) > NUM(p)) {
+      printf("%p page: %p gen: %i class: %i ALIVE\n", p, page, page->generation, page->size_class);
+      printf("%p BEGIN: %p ALLOCED_UPTO: %p\n", p, (void*) page->addr, (void*) (NUM(page->addr) + page->size));
+      fflush(stdout);
+      return 1;
+    }
+    else {
+      printf("%p page: %p gen: %i class: %i DEAD\n", p, page, page->generation, page->size_class);
+      printf("%p BEGIN: %p ALLOCED_UPTO: %p\n", p, (void*) page->addr, (void*) (NUM(page->addr) + page->size));
+      fflush(stdout);
+      return 0;
+    }
+  }
+}
+
+void GC_dbg_dump_mpage(mpage *page) {
+  printf("mpage:  %p\n", page);
+  printf("next:  %p\n", page->next);
+  printf("prev:  %p\n", page->prev);
+  printf("addr:  %p\n", page->addr);
+  printf("previous_size:  %li\n", page->previous_size);
+  printf("for med page, points to place to search for available block\n");
+  printf("size:  %li\n", page->size);
+  printf("generation:  %i\n", page->generation);
+
+  printf("back_pointers: %i\n", page->back_pointers);
+  printf("size_class: %i 1 => med; 2 => big; 3 => big marked \n", page->size_class);    ; /* */
+  printf("page_type:  %i\n", page->page_type);
+  printf("marked_on   %i\n", page->marked_on);
+  printf("has_new     %i\n", page->has_new);
+  printf("mprotected  %i\n", page->mprotected);
+  printf("added       %i\n", page->added);;
+  printf("live_size: %i\n", page->live_size);
+  printf("backgrace:  %p\n", page->backtrace);
+}
+
+int GC_dbg_dump_mpage_for_p(void *p) {
+  NewGC *gc = GC_get_GC();
+  mpage *page = pagemap_find_page(gc->page_maps, p);
+  if (page) {
+    GC_dbg_dump_mpage(page);
+    return 1;
+  }
+  else {
+    printf("Not allocated by the GC\n");
+    return 0;
+  }
+}
+
diff --git a/src/mzscheme/include/schthread.h b/src/mzscheme/include/schthread.h
index 5b21840fe4..f0765eaf44 100644
--- a/src/mzscheme/include/schthread.h
+++ b/src/mzscheme/include/schthread.h
@@ -30,7 +30,7 @@ extern "C" {
 # if _MSC_VER
 #  define THREAD_LOCAL /* empty */
 #  define IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS
-# elif defined(OS_X)
+# elif defined(OS_X) || defined(GC2_PLACES_TESTING)
 #  define IMPLEMENT_THREAD_LOCAL_VIA_PTHREADS
 #  if defined(__x86_64__) || defined(__i386__)
 #   define INLINE_GETSPECIFIC_ASSEMBLY_CODE
diff --git a/src/mzscheme/mzconfig.h.in b/src/mzscheme/mzconfig.h.in
index 0585cdf198..3e252c692c 100644
--- a/src/mzscheme/mzconfig.h.in
+++ b/src/mzscheme/mzconfig.h.in
@@ -45,4 +45,7 @@
 /* Configure use of pthreads for the user-thread timer: */
 #undef USE_PTHREAD_INSTEAD_OF_ITIMER
 
+/* Enable GC2 Places Testing: */
+#undef GC2_PLACES_TESTING
+
 #endif